A catheter having an outside diameter of 1.4 to 1.6 mm which is to be inserted into a blood vessel and used alone. This catheter includes a catheter body which has an inner layer, an outer layer and a reinforcing material layer located therebetween, and a soft tip which is provided on the distal side of the catheter body and more flexible than the catheter body. At a distal portion, the catheter body has a curved part having a curved shape which is engageable with a branched portion of a blood vessel due to the curved shape. The curved part is configured so that the average total thickness of the inner layer, the outer layer and the reinforcing material layer is 60 to 100 µm while the average minimum thickness of the outer layer is 8 to 30 µm and thus, when the curved part is pushed from the branched portion toward the distal side, it can be deformed according to the shape of the distal-side portion of the blood vessel.
